多年生黑麦草种质苗期抗旱性综合评价

对24份盆栽多年生黑麦草种质材料在苗期采用反复干旱法试验,调查了地上、地下生物量、株高、分蘖数、根冠比5个形态学指标,通过存活率、抗旱指数、隶属函数法、主成分分析、聚类分析5种方法进行了抗旱性评价。结果表明:干旱胁迫下多年生黑麦草生长受到明显抑制,所有形态指标的抗旱系数DRC均具有显著差异,可作为多年生黑麦草抗旱性评价指标,除根冠比外均与抗旱性正相关。5种评价方法结果一致,抗旱指数法为单指标评价,简单快捷;隶属函数法为综合评价法,应用面广。根据隶属函数法可将供试多年生黑麦草材料分为4类:抗旱性强的有7623,7905和7932,抗旱性较强的7406、7722、7095、7252、7484、7454,抗旱性中等的为7814、7253、7544、7431、7101、7053,抗旱性较差的有7847、7288、7530、7054、7151、7192、7840、7261、7442。

Comprehensive evaluation on drought resistant of Lolium perenne in seedling stage

The drought resistance of 24 Lolium perenne germplasm materials were evaluated in seedling stage by repeated drought method.The morphology index including the aboveground biomass,underground bio-mass,plant height and tiller number and root-shoot ratio,were measured and drought-resistance was evaluated according to survival rate,drought-resistance index(DRI),subordinate function values,principal component a-nalysis(PCA)and cluster analysis.The results indicated that the normal growth in seedling period was signifi-cantly inhibited under drought stress because the drought resistance coefficient (DRC)of all morphology index in different varieties had significant difference.Therefore,these index may be used as evaluation index.Except root-shoot ratio,these indexes had the postive correlation with the drought resistance.The results by 5 evalua-tion methods were similar.DRI were single index and simple,subordinate function values were comprehensive assessment index and wide application.According to the subordinate function values,these Lolium perenne germplasm were classified into 4 categories,the strongest stains were No.7623,No.7905 and No.7932,the stronger stanis were No.7406,No.7722,No.7095,No.7252,No.7484,No.7454,the middle stains were No. 7814,7253,No.7544,No.7431,No.7101 and No.7053,the poor stains were No.7847,No.7288,No.7530,No. 7054,No.715 1,No.71 92,No.7840,No.7261 and No.7442.